Cause analysis of flaw detection unqualified for wind power steel Q345D
The ultrasonic flaw detection for part of the wind power steel Q345D produced by Bayi Iron & Steel Co.,ltd.was unqualified.The steel plate of the flaw detection unqualified was sampled and the microstructure was examined to study the causes of the flaw detection unqualified for the steel Q345D.The results showed that there were the banded structure,the aggregation of sulfide,the bainite structure and the martensite structure in the center of the plate.The inner cracks were caused by thermal stress,structural stress and the aggregationo of harmful element,which led to the flaw detection unqualified for the Q345D steel plate.The banded structure and the central martensite could be decreased by optimizing the continuous casting process and improving the cooling process.
NETL
NSTL
万方数据
维普
